Existing comment:
Flying Tanker -- 208 B-24J and L models were converted to unarmed fuel transports under the designation C-109. All armament and bombardment equipment was removed and both the forward and aft turrets were removed and faired over with sheet metal. The waist windows were retained. Eight fuel tanks were installed inside the fuselage that could carry 2,900 US gallons. An early plan called for ten B-29 groups to be stationed in China for operations against Japan, and these bombers were to be supported by no less than 2,000 C-109s operating with the 20th Air Force flying in supplies of aviation gasoline over the Hump from India. This plan was dropped when the B-29 Superfortress operations were relocated from China to the Marianas, from where they could be better supported by US Navy seaborne tankers. In late 1944, the C-109s were transferred to the Air Transport Command. Some limited use of the C-109 was made in Europe.

Spy Plane -- The B-24 even found use a spy plane in the South Pacific. Two B-24As were designated for a secret spy flight over Japanese bases on Jaluit and Truk. If they were detected, the cover-up story would have been that the planes got "lost" while in route to the Philippines and had accidentally strayed over the islands. Before the operation could take place, Pearl Harbor was attacked. One of the planes designated for this mission was destroyed on the ground at Hickam Field during the attack, and some of the crewmembers were killed.
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